On the workflow side of production for both films and games, layered
animation has allowed for a renewed the trust of artists in the use
of motion capture as a viable tool.
In the creation of 2D images layers are use to apply changes on top
of changes in a non-destructive approach, the same approach can be
done in 3D animation.
We will try to explain this process through the hands-on exercise of
animating a feather falling to the ground using Motion Builder. A layered
approach to animation using Maya will be briefly discussed at the end
of the tutorial.

To do this tutorial you want to be somewhat familiar with the navigation
of Motion Builder.

Let’s begin by looking at a comparison
of the animation that we are going to start with and the one that
we want to end up with after we layer the enhancements.

Getting Started

Download the file Feather_Fall.fbx by following the link
at the end of this page.
Open it using Motion Builder. You will see that in the left part of
the Transport controls window there is a drop down box that reads Feather
Finish which stands for the take that is selected at the moment (fig
1).

Fig 1.

Motion Builder gives you the possibility to have different
animations for the same object inside the same file through the use
of takes.

Make sure that you have set the Playback Rate to 24fps and the loop
button is turned on, if you play the animation you will be able to
see how the project is going to look when you finish the tutorial

Base Layer

Go to the take named FeatherStart by clicking on current
take in the Transports Controls window where it says FeatherFinish (fig
2). If you play the animation you will see the feather move on a diagonal
line from the top right side of the camera onto the left side of the
grid, there is no rocking motion or rotation as it falls.

Fig 2.

Click anywhere on the viewer to make it active and press ctrl+a to
cycle through the display modes until you see the Null node named Feather
Controller and select it (fig 3).

Fig 3.

On the Navigator Window select the FCurves tab (fig4). Click on translation
to see the animation curves that have been set on the Base Layer. Even
though the animation of the feather was manually created a key has
been placed in every frame to mimic a motion capture situation.